Abstract: Alkaline earth metal oxides(MgO, CaO and BaO) were used as cracking catalysts, and a 3L cracking reactor made in the laboratory was used to crack and deoxidize acidic oil to prepare hydrocarbon fuels. The results showed that the yields of liquid fuel obtained from catalytic cracking of acidic oil by three kinds of alkaline earth metal oxides were 70%-80%; CaO and MgO as cracking catalysts could effectively deoxidize and produce more liquid fuel under lower reaction temperature and the acid value of the fuel was lower than 20 mg/g. Barium stearate, calcium stearate, and magnesium stearate was used as model compounds to study the kinetics of the pyrolysis reaction of waste oils, the thermogravimetric analysis was performed first, and then the kinetic parameters of the thermogravimetric results were calculated by using the distributed activation energy method. The results showed the pyrolysis activation energies of barium stearate, calcium stearate, and magnesium stearate decreased sequentially, which were 268, 204 and 127 kJ/mol, respectively. Above results indicated that the use of MgO as catalyst to crack acidic oil could collect more liquid fuel in the lower temperature section, and the waste oil was converted at lower temparture, which could effectively reduce the energy consumption during the conversion reaction.